Possible Premature Tire Wear? Please Help!
#17
Race Director
Update:
Had my car into the shop the other day and had them check the alignment specs:
Here are the original specs after the springs and spacers were installed back in April:
Left Rear:
Camber -1.7
Toe 0.1
Right Rear:
Camber -1.8
Toe 0.14
Rear total toe 0.24
Thrust angle -0.02
And here are the new specs from the other day:
Left Rear:
Camber -1.8
Toe 0.46
Right Rear:
Camber -1.7
Toe 0.23
Rear total toe 1.09
Thrust angle 0.19
I didn't major in alignment in university, so can any of you knowledgeable guys please chime in and let me know if these new specs sound like a reason for the excessive tire wear? Or can you recommend some lighter shoes?
Thanks!
Had my car into the shop the other day and had them check the alignment specs:
Here are the original specs after the springs and spacers were installed back in April:
Left Rear:
Camber -1.7
Toe 0.1
Right Rear:
Camber -1.8
Toe 0.14
Rear total toe 0.24
Thrust angle -0.02
And here are the new specs from the other day:
Left Rear:
Camber -1.8
Toe 0.46
Right Rear:
Camber -1.7
Toe 0.23
Rear total toe 1.09
Thrust angle 0.19
I didn't major in alignment in university, so can any of you knowledgeable guys please chime in and let me know if these new specs sound like a reason for the excessive tire wear? Or can you recommend some lighter shoes?
Thanks!
If my conversion math is right the car now has way too much rear toe and the toe difference is way out.
5' is 0.083 decimal degrees and the car has 27' in one wheel and 13.8' in the other. (13' is GT2 territory.)
If I'm right the alignment is worse now than it was and it wasn't right then.
#18
Rennlist Member
I agree with Macster and Bill. The new alignment toe-in is too much on each side, and side-to-side toe difference is also too great. The rear toe spec range for my '06 CS is .00 to .17 per side, so the midpoint of the spec range is about .08. The total toe spec range is .00 to .33 (midpoint about .16), with a thrust angle very close to zero. [My toe-in is .09, total toe is .18, and thrust angle is -.01] Your car's previous toe-in, total toe, and thrust angle were much better; and fully within the spec range. A little rear toe-in helps to settle the rear-end down, but the amount your car has now goes overboard with that, and should produce excessive tire wear.
We haven't mentioned the camber measures because they have remained within spec and look normal. Depending on usage and how much front camber they have, some may like a little less than -1.7 in the rear, and some may like a little more. Anyway, -1.7 or -1.8 is fine for most (mine is -1.8).
We haven't mentioned the camber measures because they have remained within spec and look normal. Depending on usage and how much front camber they have, some may like a little less than -1.7 in the rear, and some may like a little more. Anyway, -1.7 or -1.8 is fine for most (mine is -1.8).
#19
Rennlist Member
I have 20k miles on my '11 Boxster S, with probably 12K of that on the street [the rest on the track with track tires mounted.]
My street tires -- front and rear -- still have a good bit of tread left.
I have to agree with the many posts here that suspect your alignment is off. 1 track day [I also had 1 track day on my stock tires] can't be the culprit -- and you've worn out your tires much too soon. Faulty alignment is the likely cause.
Fred
My street tires -- front and rear -- still have a good bit of tread left.
I have to agree with the many posts here that suspect your alignment is off. 1 track day [I also had 1 track day on my stock tires] can't be the culprit -- and you've worn out your tires much too soon. Faulty alignment is the likely cause.
Fred
#20
Instructor
Thread Starter
Thanks for your replies, guys!
I'm regularly getting at least 600km (+/- 372 miles) out of a tank of gas with about 10 liters (+/-2 US gallons) left, so I don't think I'm driving the car too hard. I'm thinking the rapid tire wear has more to do with the alignment; and based on all of your responses, my initial hunch seems to be correct. Especially in light of the current alignment specs.
I am putting the car in winter storage this weekend. When I take the car out of storage next spring, I'll put new tires on and get another alignment.
In the meantime I'll be pining for spring!
Tommy
I'm regularly getting at least 600km (+/- 372 miles) out of a tank of gas with about 10 liters (+/-2 US gallons) left, so I don't think I'm driving the car too hard. I'm thinking the rapid tire wear has more to do with the alignment; and based on all of your responses, my initial hunch seems to be correct. Especially in light of the current alignment specs.
I am putting the car in winter storage this weekend. When I take the car out of storage next spring, I'll put new tires on and get another alignment.
In the meantime I'll be pining for spring!
Tommy
#21
Rennlist Member
Tommy: If you got excessive tire wear with your old alignment specs, I don't think the alignment was the problem. I suspect that your current alignment toe-in will cause excessive wear, however.